https://apo.ansto.gov.au/dspace/handle/10238/11 ANSTO authored journal articles Tue, 16 Feb 2021 06:34:08 GMT 2021-02-16T06:34:08Z https://apo.ansto.gov.au/dspace/handle/10238/10423 Title: Energy-resolved neutron imaging options at a small angle neutron scattering instrument at the Australian Center for Neutron Scattering Authors: Tremsin, AS; Sokolova, AV; Salvemini, F; Luzin, V; Paradowska, AM; Muránsky, O; Kirkwood, HJ; Abbey, B; Wensrich, CM; Kisi, EH Abstract: Energy-resolved neutron imaging experiments conducted on the Small Angle Neutron Scattering (SANS) instrument, Bilby, demonstrate how the capabilities of this instrument can be enhanced by a relatively simple addition of a compact neutron counting detector. Together with possible SANS sample surveying and location of the region of interest, this instrument is attractive for many imaging applications. In particular, the combination of the cold spectrum of the neutron beam and its pulsed nature enables unique non-destructive studies of the internal structure for samples that are opaque to other more traditional techniques. In addition to conventional white beam neutron radiography, we conducted energy-resolved imaging experiments capable of resolving features related to microstructure in crystalline materials with a spatial resolution down to ∼0.1 mm. The optimized settings for the beamline configuration were determined for the imaging modality, where the compromise between the beam intensity and the achievable spatial resolution is of key concern. © 2020 AIP Publishing LLC Tue, 26 Mar 2019 00:00:00 GMT https://apo.ansto.gov.au/dspace/handle/10238/10423 2019-03-26T00:00:00Z https://apo.ansto.gov.au/dspace/handle/10238/10421 Title: Industrial application experiments on the neutron imaging instrument DINGO Authors: Garbe, U; Ahuja, Y; Ibrahim, R; Li, H; Aldridge, LP; Salvemini, F; Paradowska, AM Abstract: The new neutron radiography / tomography / imaging instrument DINGO is operational since October 2014 to support the area of neutron imaging research at ANSTO. The instrument is designed for a diverse community in areas like defense, industrial, cultural heritage and archaeology applications. In the field of industrial application it provides a useful tool for studying cracking and defects in concrete or other structural material. Since being operational we gathered experience with industrial applications and commercial customers demanding beam time on DINGO. The instrument is a high flux facility with is 5.3 × 107 [n/(cm2s)] (confirmed by gold foil activation) for an L/D of approximately 500 at HB-2. A special feature of DINGO is the in-pile collimator position in front of the main shutter at HB-2. The collimator offers two pinholes with a possible L/D of 500 and 1000. A secondary collimator separates the two beams by blocking one and positions another aperture for the other beam. The neutron beam size can be adjusted to the sample size from 50 × 50 mm2 to 200 × 200 mm2 with a resulting pixel size from 27 μm to ∼100 μm. The whole instrument operates in two different positions, one for high resolution and one for high speed. We would like to present our first experience with commercial customers, scientific proposals with industrial applications and how to be customer ready. © 2017 The Author(s). Published by Elsevier B.V. Sun, 01 Jan 2017 00:00:00 GMT https://apo.ansto.gov.au/dspace/handle/10238/10421 2017-01-01T00:00:00Z https://apo.ansto.gov.au/dspace/handle/10238/10418 Title: Assessment of residual stress, hardness, and defect tolerance in a tee joint, as-welded and after post-weld heat treatment Authors: Law, M; Paradowska, AM; Hoye, N; Grace, P Abstract: The risk of hydrogen-assisted cold cracking (HACC) is often conflated with the risk of brittle fracture. However, if delayed non-destructive testing (NDT) shows there are no defects, or defects below the critical crack size, then brittle fracture is not possible. Post-weld heat treatment (PWHT) is known to reduce the risk of HACC but is not always possible to perform. To assess the effects of PWHT, the residual stresses and hardness values were measured before and after PWHT to assess the effects of PWHT on HACC susceptibility and on the critical defect sizes. The residual stresses were lower than code-based estimates. PWHT reduced the residual stress and hardness, and increased the critical crack size. Copyright Scientific Surveys Ltd Wed, 01 Mar 2017 00:00:00 GMT https://apo.ansto.gov.au/dspace/handle/10238/10418 2017-03-01T00:00:00Z https://apo.ansto.gov.au/dspace/handle/10238/10417 Title: Measurement of residual stresses in aluminothermic rail welds using neutron diffraction technique Authors: Khodabakhshi, B; Paradowska, AM; Ibrahim, R; Mutton, PJ Abstract: It is understood that residual stresses in aluminothermic rail welds play an important role in the fatigue behaviour of the welds. Measuring the residual stresses in the critical areas and finding the correlation between these stresses and welding parameters can be useful in order to alter the welding procedure and improve the fatigue performance of these welds. In this paper, residual stresses in the foot of the rail weld were measured using neutron diffraction and the preliminary results are presented. © 2021 by Trans Tech Publications Ltd. Sat, 01 Feb 2014 00:00:00 GMT https://apo.ansto.gov.au/dspace/handle/10238/10417 2014-02-01T00:00:00Z